The Organisation Intersex International Australia has raised concerns about the draft Human Rights and Anti-Discrimination Bill, which is before a Senate inquiry.

Its president, Gina Wilson said that while the draft bill attempts to include intersex people under the category of ''gender identity'', this is inappropriate as being intersex is a matter of biology, not gender identity.

She said it was ''vitally important'' that ''intersex'' was listed separately as a protected attribute, noting that previous attempts to bring discrimination cases under state laws - which have similar wording to the proposed federal legislation - had been rejected because the issues were not about gender identity.

Estimates of the number of intersex people vary and depend on the definition. OII Australia says an intersex person may have biological attributes of both sexes or lack some attributes considered necessary to be defined as male or female. Research by Brown University's Professor Anne Fausto-Sterling that includes chromosomal conditions such as Klinefelter and Turner syndromes estimates intersex birthrates to be about 1.7 per cent.

Ms Wilson, who is an intersex woman, says that discrimination for intersex people is a daily issue. ''We're generally considered to be freaks or weirdos,'' she said. ''People stop and stare and point and look.''

In its submission to the inquiry, OII Australia cites workplace harassment, losing work contracts, having problems booking airfares online and being pressured to have medical treatments (such as testosterone therapy), as examples of discrimination experienced by its members.

Ms Wilson said she was moved out of a female ward in a Sydney public hospital four years ago, while recovering from a hysterectomy, and put in a cleared-out storage room because other patients were uncomfortable by her ''observed differences'', including the sound of her voice.

In its submission to the inquiry, which will have public hearings this week, the Australian Human Rights Commission recommends that the bill provides protection ''more directly'' on the basis of a person's sex characteristics, intersex status, or gender expression. The Law Council of Australia supports this position.

Greens legal affairs spokeswoman, Penny Wright, who sits on the Senate committee, said there was clearly a gap when it came to protecting intersex people in the proposed laws.

''I cannot understand why there would be resistance to this change. Given this condition is in relation to physiological and anatomical differences. [Intersex people] don't have any choice about it,'' Senator Wright said.

A spokesperson for acting Attorney-General Jason Clare said the government would look at the Senate inquiry's findings.

''If the Senate inquiry identifies improvements or amendments to the current drafting, the government will closely consider those recommendations,'' the spokesperson said.